Reflections in Nature: Carnivorous plants in PA
Do you remember the musical “The Little Shop of Horrors”? The story was about a florist shop worker who raised a plant that fed on human blood and flesh.
Although in reality there is no plant that feeds upon humans, there are 670 species of carnivorous plants worldwide and, here in Pennsylvania, we have 14 species of carnivorous plants, including sundews, pitcher plants and bladderworts.
Bladderwort, which is a carnivorous plant that grows in water, lacks roots and usually has a horizontal floating stem bearing either simple or divided leaves.
Small carnivorous bladders produced along the stem can range from a dark color to transparent.
If a small insect triggers the bristles that project from the surface of the bladder door, the trap suddenly opens and, with a quick inflow of water, the insect is drawn inside. The door closes quickly, and the creature is digested.
Within 15 to 30 minutes, water passes out of the bladder, and the trap is reset.
In Pennsylvania, we have 11 species of bladderwort, with five considered rare.
Worldwide, there are 90 species of sundews — mostly in Australia and South Africa — and Pennsylvania is home to two native sundew species.
This plant’s name comes from its leaves. Each leaf’s surface has attached tentacles that are covered with glistening droplets that appear as dew; however, they actually are a mixture of sticky substances and digestive enzymes secreted by the plant’s tentacles.
After a small insect lands on the sticky substance, it becomes unable to escape, causing the tentacles to bend and imprison the insect. The enzymes in the dew begin to dissolve and reduce the insect to amino acids and nutrients that can be readily absorbed by the plant.
Once the meal is completed, the leaf will re-open and the tentacles will reset.
Back in 1998, I had information on the location of pitcher plants growing in a bog on Ellington Mountain. Although I had read about these interesting carnivorous plants, I had never seen any in the wild. A few days later I decided to check out the information and, after two tries, I found the bog. It was hard to believe that I actually was seeing thousands of pitcher plants growing in the swamp.
This past Sunday I decided to revisit the bog to take pictures of the plant for this column. However, in the 18 years since my last visit, the trail no longer was visible, the stream evidently dried up, and I was unable to locate the site.
Pitcher plants grow in areas such as bogs and swamps, where very few plants can survive due to low nitrogen content. The pitcher plant is able to withstand this low nitrogen condition because it is a carnivorous plant, using small insects to supplement its diet.
Small insects are attracted to the sweet substance found on the edge of the plant’s leaves. The leaf’s inside surface is slippery and has hairs pointing downward so that once an insect lands inside the leaf, it cannot escape.
Located in the bottom of the leaf is a pool containing rain water, which has a high amount of enzymes produced by the plant. After an insect falls into the liquid, its body quickly is broken down by the enzymes, making it easier for the plant to absorb.
Some spiders and even small frogs and lizards wait near the plant’s entrance, hoping to snatch unwary victims that come to investigate the sweet smell of the plant’s leaves.
The hollow leaves resemble pitchers, giving the plant its common name of pitcher plant. It also has many more names, such as huntsman’s-cap, whippoorwill’s-boots, Adams-pitcher, fever-cup, small-pox plant, flytrap and side-saddle flower.
There are about 10 species of pitcher plants in the genus Sarracenia, all of which are native to North America. The scientific name is Sarracenia purpura. “Sarracenia” comes from J. A. Sarrasin, the 17th century botanist who discovered the plant and sent it to France. The species name of purpura is Latin and means “purple,” in reference to the plant’s leaves, which are broadly winged, hooded leaves, 4 to 10 inches long and purple-veined.
The leaves of the pitcher plant are not long-lived, surviving only a year or two. They vary in color from a deep purple to a light yellow-green, with deep purple veins.
The pitcher plant that grows in Pennsylvania has an open hood, which allows rainfall to enter the tube; most other pitcher plants have a hood that bends over the tube, which allows insects to enter but keeps rain water out.
The plant’s flowering season is May and June. The flowers are a deep, reddish purple color or, at times, a partly greenish or pink color.
Bower retired after 34 years as a wildlife conservation officer for the state Game Commission. Questions and comments may be sent to him at 1224 Redington Ave., Troy PA 16947.